Structural Phase Stability Research Articles

Nitrogen‐Doped Cobalt Diselenide with Cubic Phase Maintained for Enhanced Alkaline Hydrogen Evolution

AbstractThe introduction of heteroatoms is one of the most important ways to modulate the intrinsic electronic structure of electrocatalysts to improve their catalytic activity. However, for transition metal chalcogenides with highly symmetric crystal structure (HS‐TMC), the introduction of heteroatoms, especially those with large atomic radius, often induces large lattice distortion and vacancy defects, which may lead to structural phase transition of doped materials or structural phase reconstruction during the catalytic reaction. Such unpredictable situations will make it difficult to explore the connection between the intrinsic electronic structure of doped catalysts and catalytic activity. Herein, taking thermodynamically stable cubic CoSe2 phase as an example, we demonstrate that nitrogen incorporation can effectively regulate the intrinsic electronic structure of HS‐TMC with structural phase stability and thus promote its electrocatalytic activity for the hydrogen evolution activity (HER). In contrast, the introduction of phosphorus can lead to structural phase transition from cubic CoSe2 to orthorhombic phase, and the structural phase of phosphorus‐doped CoSe2 is unstable for HER.

The investigation of the half-metallic properties of half-Heusler KXP (X = Cr & Mo) compounds: A first-principles study

In this article, the structural phase stability of the KXP (X = Cr & Mo) compounds in the half-Heusler structure were investigated. The stability of the KXP compound was taken into account in the three phases α, β, and γ of the half-Heusler structure within various ferromagnetic (FM), antiferromagnetic (AFM), and nonmagnetic (NM) states. Total energy calculations, as well as cohesive energy calculations, indicated that for each KXP compound the β phase of the half-Heusler structure in the FM state has the lowest energy compared to the other phases α and γ. For all structural phases of the KMoP compound, the positive amount of the formation energy predicts that the compound cannot be grown in the hypothetical half-Heusler structure and prefers to decompose into stable phases of the constituent elements. The hull distance calculations justify that, unlike KMoP, the β and γ phases of the half-Heusler KCrP compound can be considered to be thermodynamically stable and suitable for experimental synthesis. Based on the elastic results, it can be argued that, unlike α phase, both β and γ phases of the KCrP compound in the FM state satisfy the conditions of mechanical stability. Moreover, γ phase of the KCrP compound is stiffer than β phase, while β phase has a more ductile nature compared to γ phase. In agreement with the elastic results, the phonon scattering calculations showed that both β and γ phases of the half-Heusler KCrP compound are dynamically stable and can be synthesized, while the α phase is regarded to be an unstable phase. The electronic calculations indicated that the KCrP compound in the different phases β and γ possess a half-metallic property with the highly desired Curie temperature, making it a potential candidate for use in spintronic devices.

Phase Diagram and Cation Dynamics of Mixed MA1–xFAxPbBr3 Hybrid Perovskites

We use a multi-technique approach to determine the phase diagram and molecular cation dynamics of mixed methylammonium-formamidinium MA1-xFAxPbBr3 (0 ≤ x ≤ 1) hybrid perovskites. The calorimetric, ultrasonic and X-ray diffraction experiments show a substantial suppression of the structural phase transitions and stabilization of the cubic phase upon mixing. We use the broadband dielectric and Raman spectroscopies to study the MA and FA cations dynamics in these compounds. The broadband dielectric spectroscopy indicates absence of the MA cation ordering and a gradual increase of the rotation barrier upon mixing. The room-temperature dielectric permittivity substantially decreases as the fraction of the FA cations is increased. No significant changes of the permittivity are detected at temperatures where the dielectric relaxations are absent. We also observe weak signatures of a dipolar glass phase for the highest mixing level (x = 0.5). The Raman spectroscopy supports the dielectric results and reveals additional subtle information about the FA cation dynamics.

Enhanced aging behaviors and electric thermal stabilities in 0.75BiFeO3–0.25BaTiO3 piezoceramics by Mn modifications

AbstractLead‐free 0.75BiFeO3–0.25BaTiO3 (0.75BF–0.25BT) ceramics have been extensively studied because of their high Curie temperature. The aging behavior and thermal stability of piezoceramics play decisive roles in their device applications. In this work, effects of Mn doping on the phase structure, aging behavior, and thermal stability of 0.75BF–0.25BT ceramics were characterized and related mechanisms were investigated. With the increase in Mn content, the typical rhombohedral phase of 0.75BF–0.25BT ceramics changed to the coexistence of pseudo‐cubic and rhombohedral phases. Mn modification enhanced the aging behavior and thermal stability of ceramics obviously. The aging rates of d33 and kp for 0.75BF‐0.25BT ceramics with 1.0 mol% Mn are 1.3% and 1.1%, respectively, which are only 1/4 those values for the undoped ceramics. The variation of εr of 0.75BF‐0.25BT ceramics with 1.0 mol% Mn is half of undoped ceramics under 500℃. The depoling temperature of 0.75BF‐0.25BT ceramics with 1.0 mol% Mn was 450℃, which is about 200℃ higher than that of undoped ceramics. The enhanced aging behavior results from the decreased defect concentrations, and the better thermal stability is owing to the significantly improved poling state due to the enhanced resistivity, large grain size, and decreased crystal distortion by Mn modification. These results reflect that a proper amount of Mn doping is an effective way to enhance the aging behavior and electric thermal stability.

In-situ thermal phase transition and structural investigation of ferroelectric tetragonal barium titanate nanopowders with pseudo-cubic phase

Optimization and miniaturization of existing electronic devices require the development of advanced nanostructured materials with high phase and structural purity. Over the past decade, barium titanate (BaTiO3) has attracted considerable attention due to its outstanding ferroelectric and dielectric properties. The present study involved the investigation of the phase transition and structural stability of tetragonal BaTiO3 nanopowders with pseudo-cubic phase using an in-situ high resolution and high temperature X-ray diffraction method. Under ambient conditions, the coexistence the tetragonal and cubic phases with weight fractions of 75.7% and 24.3%, respectively, was determined in BaTiO3. In the temperature range of 25 °C-300 °C, phase boundaries of BaTiO3 (180 nm in size) exhibiting several phases were detected. The phase transformation behavior, relative crystal phase content, lattice parameters, crystallite size, and tetragonality of the BaTiO3 nanopowders were established by the Rietveld refinement method at the onset temperature from 25 °C to 300 °C. Up to 150 °C, the nanopowders exhibited a complete transition of the cubic phase. Additionally, a complete tetragonal to cubic transformation was accomplished by a decrease of tetragonality at 125 °C and an increase in the crystallite size at 300 °C.

Insights into the Correlation between Tetragonal Phase and Temperature Stability of Potassium Sodium Niobate Based Ceramics from Domain Behaviors

AbstractThe temperature stability of tetragonal phase, as an indispensable end component of polymorphic phase boundary in high performance potassium sodium niobate based ceramics, has been long‐term neglected. Aimed at resolving the most cutting‐edge challenges for the practical application of potassium sodium niobate (KNN)‐based ceramics, the association study between tetragonal phase and its temperature stability is focused upon, especially from a microscopic point of view. Here, four kinds of potassium sodium niobate based ceramics with orthorhombic, tetragonal, orthorhombic–tetragonal, and rhombohedral–orthorhombic–tetragonal phase boundaries are designed, and investigations from macro properties as well as the underlying domain behaviors are conducted to establish the relationship between phase structure and temperature stability. Polarization retention with aging time and domain dynamics under thermal excitation suggest that tetragonal phase is closely related to the temperature sensitivity because of their instable and fast back‐switching properties of the reoriented domains. It is believed that a new perspective in the future designing of temperature‐insensitive ceramics is put up.

Ultrathin 2D-oxides: A perspective on fabrication, structure, defect, transport, electron, and phonon properties

In the field of atomically thin 2D materials, oxides are relatively unexplored in spite of the large number of layered oxide structures amenable to exfoliation. There is an increasing interest in ultrathin film oxide nanostructures from applied points of view. In this Perspective paper, recent progress in understanding the fundamental properties of 2D oxides is discussed. Two families of 2D oxides are considered: (1) van der Waals bonded layered materials in which the transition metal is in its highest valence state (represented by V2O5 and MoO3) and (2) layered materials with ionic bonding between positive alkali cation layers and negatively charged transition metal oxide layers (LiCoO2). The chemical exfoliation process and its combination with mechanical exfoliation are presented for the latter. Structural phase stability of the resulting nanoflakes, the role of cation size, and the importance of defects in oxides are discussed. Effects of two-dimensionality on phonons, electronic band structures, and electronic screening are placed in the context of what is known on other 2D materials, such as transition metal dichalcogenides. The electronic structure is discussed at the level of many-body-perturbation theory using the quasiparticle self-consistent GW method, the accuracy of which is critically evaluated including effects of electron–hole interactions on screening and electron–phonon coupling. The predicted occurrence of a two-dimensional electron gas on Li-covered surfaces of LiCoO2 and its relation to topological aspects of the band structure and bonding is presented as an example of the essential role of the surface in ultrathin materials. Finally, some case studies of the electronic transport and the use of these oxides in nanoscale field-effect transistors are presented.

Effects of Transition Elements on the Structural, Elastic Properties and Relative Phase Stability of L12 γ′-Co3Nb from First-Principles Calculations

In order to explore novel light-weight Co-Nb-based superalloys with excellent performance, we studied the effects of alloying elements including Sc, Ti, V, Cr, Mn, Fe, Ni, Y, Zr, Mo, Tc, Ru, Rh, Pd, Hf, Ta, W, Re, Os, Ir and Pt on the structural stability, elastic and thermodynamic properties of γ′-Co3Nb through first-principles calculations. The results of transfer energy indicate that Y, Zr, Hf and Ta have a strong preference for Nb sites, while Ni, Rh, Pd, Ir and Pt have a strong tendency to occupy the Co sites. In the ground state, the addition of alloying elements plays a positive role in improving the stability of γ′-Co3Nb compound. The order of stabilizing effect is as follows: Ti > Ta > Hf > Pt > Ir > Zr > Rh > V > Ni > W > Sc > Mo > Pd > Re > Ru. Combining the calculation results of elastic properties and electronic structure, we found that the addition of alloying elements can strengthen the mechanical properties of γ′-Co3Nb, and the higher spatial symmetry of electrons accounts for improving the shear modulus of γ′-Co3Nb compound. At finite temperatures, Ti, Ta, Hf, Pt, Ir, Zr and V significantly expand the stabilization temperature range of the γ′ phase and are potential alloying elements to improve the high-temperature stability of the γ′-Co3Nb compounds.

Transesterification of Litsea cubeba kernel oil to biodiesel over zinc supported on zirconia heterogeneous catalysts

An effective approach for synthesizing green and sustainable biodiesel fuel from low-value vegetable oils has been explored. Herein, a series of catalysts of zinc supported on zirconia (xZn/ZrO2) were successfully synthesized, characterized, and applied for the production of biodiesel from Litsea cubeba kernel oil (LCKO) through the transesterification process. The results showed that the monoclinic phase structure of the prepared catalysts transformed to the more stable tetragonal phase structure after supporting different Zn loadings (≥5%). Compared with the pure ZrO2, the highly dispersed Zn species on the surface of xZn/ZrO2 could be divided into Zn oxide and ZnOH+, which could promote the transesterification of LCKO. Thus, the 7%Zn/ZrO2 catalyst exhibited the best catalytic activity of the LCKO conversion 82.5%, which was attributed to the positive effects of both the ZrO2 support and Zn species. Furthermore, the various reaction parameters (such as reaction time, stirring rate, nCH3OH:nLCKO, catalyst amount, and reaction temperature) were investigated systematically and optimized carefully. And a possible mechanism of the transesterification process catalyzed by Zn/ZrO2 catalysts was also proposed. Finally, the physical properties of the as-synthesized biodiesel accorded with the current international biodiesel standards.

Low-temperature Mossbauer studies of the phase composition and structural stability of iron (III) oxide/hydroxide nanocomposite

In article present the results of low-temperature Mossbauer studies of iron (III) oxide/hydroxide nanocomposite synthesized by the method of deposition. Based on these studies, the composition of the synthesized composite was revealed. The nanodispersed composite with a specific surface 280 m2/g is a hematite in the weakly disordered crystalline state (CSR 10 nm), and a lepidocrocite in the X-ray amorphous state (particles size 3-4 nm). The relative integral intensity of the Zeeman sextet, which corresponds to the magnetically ordered phase of hematite, is practically unchanged and is about 17%. The tendency to divide the magnetically ordered component into two sextets, which differ in quadrupole splitting QS= –0.21 mm/s and QS= 0.21 mm/s, respectively, is observed starting from a temperature of 190 K. As a result of annealing of the synthesized material at a temperature of 200°C, a slight redistribution (≈ 5%) of the content of paramagnetic and magnetically ordered components was recorded, which indicates the structural stability of the nanoparticles of the lepidocrocite γ-FeOOH phase at this temperature. Increase of annealing temperatures to 500oC leads to the predicted course of the phase transition γ-FеООH ® α-Fе2О3. The mechanism of growth of hematite crystallites during sintering due to fixation side faces of larger α-Fe2O3 phase of nanoparticles of the γ-FeOOH phase with simultaneous transformation of their crystal structure to side faces of larger α-Fe2O3 phase particles is presented.

A novel Ce3Zr5O16 composite with gradient distribution of elements and its application in Pd-only three-way catalyst

To equilibrate the conflict between the thermal stability and redox property of ceria-zirconia mixed oxide (CZ), a novel Ce3Zr5O16 composite with gradient distribution of elements (CZ-tcp) was prepared by two-step coprecipitation and compared with the sample (CZ-cp) obtained from conventional coprecipitation method. The distribution of elements, structural and textural properties, and redox properties of samples were investigated by HAADF-STEM equipped with EDS, XPS, XRD, Raman, SEM, N2 physisorption, oxygen storage capacity and H2-TPR systematically. The results revealed that, with respect to CZ-cp, CZ-tcp exhibits more stable phase structure, and less attenuation rates of pore volume (40.1% vs 67.9%) and oxygen storage capacity (1.0% vs 18.7%) after ageing treatment, which is on account of Zr enriched in the core of the grains and Ce enriched at the surface layer of the grains. Based on this, the catalytic performance evaluation results revealed that the catalyst supported on CZ-tcp (Pd@CZ-tcp) presents improved catalytic activity of HC and NO, and better thermal stability of CO catalytic activity compared with Pd@CZ-cp. Therefore, this designed CZ-tcp shows enhanced thermal stability and redox property at the same time and can be used as a competitive oxygen storage support for three-way catalyst.

Thermal cycling behavior of EB-PVD rare earth oxides co-doping ZrO2-based thermal barrier coatings

Novel ceramic topcoat of Gd2O3–Yb2O3–Y2O3 co-stabilized ZrO2 (GYbYSZ) thermal barrier coatings were fabricated via EB-PVD technique. The phase structural stability, phase constituent, chemical composition, morphology and cyclic oxidation of the thermal barrier coatings (TBCs) were systematically studied. Based on the XRD results, the GYbYSZ ceramics has not undergone phase transformation upon long-term annealing at 1373 K and 1523 K. Although the chemical content of the GYbYSZ ceramic coat deviates from the stoichiometric value, the coating is mostly composed of cubic phase, which is accord with the XRD pattern of the original ingot. A pyramidal-like morphology appears in the microtexture of the column tips and the measured diameters of the pyramids are about 2.5~4 μm. After thermal cycling, the surface of the coating presents a multi-layer structure, which is followed by layer-by-layer spallation. The failure zone of the ceramic coats is possible to occur the interior of the thermally grown oxide (TGO) layer, or within the top ceramic coat at the interface of bond coat/TGO layers. The degradation of GYbYSZ TBCs is primarily attributed to the accumulation and relaxation of residual stress, propagation of vertical through microcracks, the growth rumpling of TGO layer, the ridges of grain boundary and the abnormal oxidation of bond coat.

Hydrogen Transportation Behaviour of V-Ni Solid Solution: A First-Principles Investigation.

Hydrogen embrittlement causes deterioration of materials used in metal–hydrogen systems. Alloying is a good option for overcoming this issue. In the present work, first-principles calculations were performed to systematically study the effects of adding Ni on the stability, dissolution, trapping, and diffusion behaviour of interstitial/vacancy H atoms of pure V. The results of lattice dynamics and solution energy analyses showed that the V–Ni solid solutions are dynamically and thermodynamically stable, and adding Ni to pure V can reduce the structural stability of various VHx phases and enhance their resistance to H embrittlement. H atoms preferentially occupy the characteristic tetrahedral interstitial site (TIS) and the octahedral interstitial site (OIS), which are composed by different metal atoms, and rapidly diffuse along both the energetically favourable TIS → TIS and OIS → OIS paths. The trapping energy of monovacancy H atoms revealed that Ni addition could help minimise the H trapping ability of the vacancies and suppress the retention of H in V. Monovacancy defects block the diffusion of H atoms more than the interstitials, as determined from the calculated H-diffusion barrier energy data, whereas Ni doping contributes negligibly toward improving the H-diffusion coefficient.

High-temperature and long-term stability in Co/Sb-codoped (Bi0.5Na0.5)TiO3-based electrostrictive ceramics

In this study, we report lead-free Co/Sb-codoped (Bi0.5Na0.5)TiO3-based ceramics with enhanced electrostrictive properties and high-temperature and long-term stability. The effect of Co/Sb codoping on the phase structure, electrical properties, and thermal stability of (Bi0.5Na0.5)TiO3-based ceramics was studied. The Co/Sb codoping induced the phase transition from the coexisting rhombohedral (R) − tetragonal (T) phase to the single pseudocubic (Pc) symmetry and the disruption of the long-range ferroelectric order of the ceramics, yielding enhanced electrostrictive properties. A large electrostrictive response was obtained in the sample with 0.02 Co/Sb content, with electrostrictive coefficients Q33 of 0.022–0.024 m4/C2 and electro-strains of 0.35–0.46% under different strengths of the electric field. The electrostrictive material exhibited temperature-insensitive and fatigue-free behavior after up to 105 cycles from room temperature to 120 °C, rendering it a promising material for high-temperature and long-term stability actuator applications.

The Site Preferences of Transition Elements and Their Synergistic Effects on the Bonding Strengthening and Structural Stability of γ′-Ni3Al Precipitates in Ni-Based Superalloys: A First-Principles Investigation

Advanced mechanical properties of Ni-based superalloys strongly depend on the site preferences of alloying X elements in γ′-Ni3Al-X precipitates, which are associated with the partial bonding characteristics between Ni, Al, and X atoms. Therefore, in the current work, the site occupancy tendencies of transition X metals were revealed via first-principles ab initio calculations at 0 K. Bonding features of Ni-Al, Ni-X, and Al-X pairs were simulated by using the charge density difference (CDD), electron localization function (ELF), and density of states (DOS) methods, respectively. According to simulations, higher atomic size X elements preferably occupy Al sites of γ′-Ni3Al-X intermetallics and lead to strong covalent-like directional bondings between themselves and their nearest neighbor (NN) Ni atoms along 〈110〉 directions. However, if these larger X metals substituted for Ni sites, the bonding properties would differ by plane due to the nature of the L12-type crystal structure of γ′-Ni3Al-X precipitates. Considering all transition elements, refractory metals (i.e., X = Re, W, Mo, Ta, or Nb) appear as the most effective strength inducers, improving the structural stability of γ′ phase, even if Ni site substitution of X = Re atoms would start to increase structural instability. On the other hand, relatively small alloying X elements having electron configuration similarities with Ni (i.e., X = Co, Cu, Rh, Pd, Ag, Ir, Pt, or Au) are more likely to worsen bonding strengthening. Instead, these transition X metals creating metallic bondings with NN Ni atoms would contribute to ductility and malleability of Ni-based superalloys. Furthermore, depending on the relative atomic size of γ′-former and refractory elements, the phase and site preferences of refractory atoms would alter in multicomponent systems. As a result of the attractive or weak repulsive forces between Re-Re, Re-Mo, and Re-W pairs, the structural stability of the constituent phases would deteriorate and harmful topologically close-packed (TCP) phases would precipitate.

Insight into the structural stability and overall performances of V2REAl20 ternary phases

In order to expand the applications of aluminum alloy, the ternary aluminum-based intermetallics have attracted the attentions of scientists. In present work, the overall performances of V2REAl20 (RE = Ho, Gd, Ce, La, Y, and Sc) were explored by DFT investigations. The thermodynamic data, lattice vibrations and volume change curves illustrate that six ternary phases are structurally stable. The values of elastic modulus and elastic constants demonstrate that V2REAl20 compounds display the better mechanical properties than aluminum. The 3D and 2D curves constructions and anisotropic indexes explain that V2REAl20 compounds possess the weak anisotropy. Moreover, the thermodynamic curves indicate that ternary V2REAl20 compounds have the better physical properties than aluminum with the elevated temperatures. In the meantime, we provided the discussion in comparison to the results of ternary Ti2REAl20 compounds.

Enhancement of Corrosive-Resistant Behavior of Zn and Mg Metal Plates Using Biosynthesized Nickel Oxide Nanoparticles

In this work, nickel oxide nanoparticles (NiO NPs) were synthesized using ultrasonic wave-assisted green synthesis route with Delonix elata leaf extract as a reducing and capping agent. The phase structure, crystallinity, thermal and physical stability, surface morphology, and surface area of the produced NiO NPs were investigated using X-ray diffraction, field-emission scanning electron microscopy high-resolution transmission electron microscopy, thermogravimetric/differential thermal analysis, and Brunauer–Emmett–Teller analysis. The surface properties such as roughness and hardness of NiO NP-coated plates were determined using atomic force microscopy and nanoindentation techniques. The electrochemical corrosion behavior of NiO NPs was studied in the presence of an aqueous electrolyte medium, that is, 3.5% NaCl, 6 M KOH, 1 M HCl, and 1 M H2SO4. The Tafel plot showed that the corrosive nature of Zn and Mg plates significantly decreases when the plates were coated with the prepared high surface area and mesoporous NiO NPs under all electrolytes, especially in acidic medium, that is, 1 M H2SO4.

Correct Structural Phase Stability of FeS2, TiO2, and MnO2 from a Semilocal Density Functional

The structural phase stabilities of iron disulfide (FeS2), titanium dioxide (TiO2), and polymorphs of manganese oxides (MnO2) are known to be challenging problems for the semilocal exchange-correlation (xc) approximations of the Density Functional Theory. Popular and nonempirical semilocal xc functionals fail badly for at least one of these solids. For example, the strongly constrained and appropriately normed (SCAN) meta-GGA xc functional fails to predict the correct ground state for FeS2 (pyrite and marcasite polymorphs) and TiO2 (rutile and anatase polymorphs) structures but yields accurate formation energies and the correct ground state of all MnO2 polymorphs. In this work, we find that the recently proposed meta-GGA constructed from the cuspless hydrogen exchange hole density (MGGAC) [Phys. Rev. B 2019, 100, 155140] can predict the correct ground state of polymorphs of FeS2, TiO2, and MnO2. Moreover, when compared to the experimental results, we also obtain the quantitatively good agreement from the MGGAC functional for the structural properties and bandgaps of those solids, and this agreement indicates the feasibility of this method.

Ab initio predictions of structure and physical properties of the Zr2GaC and Hf2GaC MAX phases under pressure

The electronic structure, structural stability, mechanical, phonon, and optical properties of Zr2GaC and Hf2GaC MAX phases have been investigated under high pressure using first-principles calculations. Formation enthalpy of competing phases, elastic constants, and phonon calculations revealed that both compounds are thermodynamically, mechanically, and dynamically stable under pressure. The compressibility of Zr2GaC is higher than that of Hf2GaC along the c-axis, and pressure enhanced the resistance to deformation. The electronic structure calculations reveal that M2GaC is metallic in nature, and the metallicity of Zr2GaC increased more than that of Hf2GaC at higher pressure. The mechanical properties, including elastic constants, elastic moduli, Vickers hardness, Poisson’s ratio anisotropy index, and Debye temperature, are reported with fundamental insights. The elastic constants C11 and C33 increase rapidly compared with other elastic constants with an increase in pressure, and the elastic anisotropy of Hf2GaC is higher than that of the Zr2GaC. The optical properties revealed that Zr2GaC and Hf2GaC MAX phases are suitable for optoelectronic devices in the visible and UV regions and can also be used as a coating material for reducing solar heating at higher pressure up to 50 GPa.

Bond characteristics and microwave dielectric properties of high‐Q materials in li‐doped Zn3B2O6 systems

AbstractThe bond characteristics, Raman spectroscopy, and microwave dielectric properties of Zn3‐xLi2x(BO3)2 ceramics prepared by solid‐state reaction method were investigated. According to the complex chemical bond theory, the bond ionicity and lattice energy of the B–O bond were proved to contributed more to the electric polarization and phase structure stability than that of A‐site bond. Thus, the B–O bond had a dominant effect on the dielectric constant and Q × f values. The optimization of the τf value can be attributed to the bond valence. Moreover, the shift and full width at half maximum of the Raman peak were closely related to the dielectric constant and Q × f values, respectively. On the whole, Li+ substitution contributed greatly to improve the temperature stability and reducing the dielectric loss of Zn3‐xLi2x(BO3)2 ceramics. Additionally, Zn2.99Li0.02(BO3)2 ceramics sintered at 850 °C exhibited satisfactory microwave dielectric properties of εr=6.59, Q × f=122,030 GHz, τf=−76.9 ppm/°C, and had good chemical compatibility with silver.